1. Field of the Invention
The invention relates to a reactor provided in an electric vehicle, a hybrid vehicle, or the like.
2. Description of the Related Art
In general, in a reactor in an electric power conversion circuit, a reactor core, which has a substantially long ring shape in a plan view, is provided, and a coil is formed around each of two longitudinal portions of the reactor core. The reactor in this state is housed in a case. The reactor core includes partial cores. Each of the partial cores is formed by a stacked body formed of a plurality of electromagnetic steel plates, or by a powder magnetic core. A gap plate formed of a nonmagnetic material is provided between the partial cores. The gap plate is fixed to the partial cores by an adhesive agent. Thus, the reactor core is formed.
A heat sink is provided on the lower surface (bottom surface) of the case. Further, a cooling block is provided under the case. A coolant or air is supplied into the cooling block. In general, heat generated in the coil or the reactor core when an electric current is applied to the coil is released to outside using the heat sink and the cooling block, while the coil and the reactor are cooled. A resin molded body is formed to seal an area between the case and the reactor core housed in the case. Thus, heat is transmitted from the coil or the reactor core to the heat sink via the resin molded body.
A method of manufacturing the reactor in related art includes a large number of processes, for example, a process in which the case is manufactured, a process in which the reactor core including the coil (or a coil bobbin) is housed in the case with the heat sink being disposed under the reactor core, a process in which the resin molded body is formed in the case after the reactor core and the heat sink are housed in the case, and a process in which, for example, grease is applied to the reverse surface of the bottom plate of the case, and then the cooling block is fitted to the reverse surface. Thus, it is important and required to increase the manufacturing yield of the reactor, in mass production of the hybrid vehicle or the like.
A large electric current and a large voltage are generally applied to the reactor provided in the electric vehicle, the hybrid vehicle, or the like. Therefore, the vibration of the reactor is large, and noise due to the vibration is large. Thus, it is urgently required to develop a reactor in which the vibration is effectively suppressed, as well as to increase the manufacturing yield and to increase the heat radiation performance.
For example, Japanese Patent Application Publication No. 2004-95570 (JP-A-2004-95570) describes a reactor device developed to increase the heat radiation performance. In the reactor device, a reactor core is placed on a holding portion of a base that serves as a heat sink, and the reactor core is fixed to the base using a fixing member. The reactor core and the base in this state are integrated with each other using unsaturated polyester. Thus, the reactor device is produced by mold forming.
In the above-described reactor device, heat generated in the reactor core is effectively radiated to the base via the holding portion and a resin molded body. However, in this reactor device as well, the vibration caused when the reactor device is operated is not sufficiently suppressed, as in other reactor devices in related art. Further, it is difficult to increase the manufacturing yield of the reactor device by simplifying the processes for manufacturing the reactor device.